Burner assembly



W. W. WILLIAMS BURNER ASSEMBLY Nov. 14, 1933.

Filed May .27. 1951 2 Sheets-Sheet 1 INVENTOR W/ILTER M. WILL/HMS BY 4 gi Z ATTORN EY Nov. 14, 1933. w. w. WILLIAMS 1,934,755

BURNER ASSEMBLY Filed May 27, 1931 2 Sheets-Sheet 2 ll l l l lfl l i hllF E-4- "FEE- mun i: m

Z I 2.5-} INVENTOR WHL 75/? w. WILL m/vs 5 F E-m- MMW Patented Nov. 14,1933 UNITED STATES PATENT OFFICE This invention relates to improvementsin fluid fuel burning mechanisms and more particularly to that mechanismwhich relates to the production of the flame, customarily called in thetrade, the burner assembly.

In fluid fuel burners of the type in which the fuel is delivered. underpressure through a fuel pipe within a surrounding air or draft pipe todischarge the fuel at the open end of the draft pipe through a nozzle toatomize the fuel in the presence of air under pressure forced throughthe draft pipe, when the fuel ignites, considerable noise caused by thecombustion occurs, and if the flame burns in close proximity to the endof the nozzle, the nozzle not only becomes heated and,

the heat from the nozzle and flame is suflicient to carbonize upon thenozzle such particles of the atomized fuel which may collect thereon asa result of eddies in the air current during the operation of theburner, or may have collected thereon by oozing from the nozzle openingwhile the burner is idle, such carbonization being liable to encroachupon the nozzle opening and eventually clogging it and preventingeflicient, and at times, the entire discharge of the fuel.

It is an object of this invention to produce a device of this characterwhich will reduce the noise of combustion, permit the flame to burn at afixed distance in advance of the nozzle, and eliminate the possibilityof carbonization of the fuel upon the end of the nozzle.

With these and other objects in view, reference is had to theaccompanying sheets of drawings which illustrate preferred embodimentsof this invention, with the understanding that minor detail changes maybe made therein without departing from the scope thereof.

In the drawings:

Figure 1 is a fragmentary view in side elevation of a portion of a draftpipe with parts broken away illustrating partly in section and partly inside elevation the operative parts of the burner assembly.

Figure 2 is an enlarged view in end elevation of the nozzle and of thedraft pipe.

Figure 3 is an enlarged View in section taken upon the line 3--3, Figure1, looking in the direction of the arrows.

Figure 4 is an enlarged detail view of the nozzle illustrated in Figure2 with parts broken away illustrating the nozzle in vertical centralsection and the contained oil spiral in elevation.

Figure 5 is a view in elevation of the left hand end of Figure 4.

Figure 6 is a view in elevation of the right hand end of Figure 4.

Figure 7 is a view in vertical central section of the oil spiral.

Figure 8 is a view in elevation of the left hand 30 end of Figure '7.

Figure 9 is a view in elevation of the right hand end of Figure 7.

Figures 10 and 11 are views corresponding to Figure 9 of modified formsthereof.

Figure 12 is a view in side elevation of a modified form of nozzle.

Figure 13 is a view in central longitudinal vertical section of Figure12 illustrating a modified form of oil spiral in place within thenozzle.

Figure 14 is a view in end elevation of the modified form of oil spiralillustrated in Figure 13.

While this invention may be applied to various types of oil burnermechanism, it has been successfully demonstrated in connection with thattype of oil burning mechanism disclosed in this applicants prior pendingapplication, Serial No. 435,424, filed March 13, 1930 which matured intoPatent No. 1,831,277, November 10, 1931, and for convenience, thedrawings illustrate an embodiment of this invention in such a type offluid fuel burner.

Since this invention relates only to that part of a fluid fuel burnercalled the burner assembly, it is not thought necessary to illustrate ordescribe a complete burner and therefore reference is made to thedisclosure in this applicant's said prior application.

Figure 1 illustrates a portion of the draft pipe 1 which supports uponone side a casing 2 enclosing a chamber 3 for the reception of the fluidfuel under pressure delivered through pipe 4. The fluid fuel isdelivered from this chamber under the pressure of the air to the nozzle5 preferably in the manner disclosed in the applicants said priorapplication, that is by pro-. viding a fluid fuel pipe 6 which isarranged centrally of the draft pipe and leads from the nozzle to theinterior of the chamber 3, terminating near the bottom thereof andprovided with a graduated port 7 surrounded by a valve sleeve 8controlled by a float 9 to increase the opening of the port as the levelof the fluid fuel within the chamber rises. The air accumulating in thechamber 3 above the level of the fuel is conveyed through the port 10through an air pipe 11 surrounding the fuel pipe 6 to the nozzle 5.

The fluid fuel is discharged through the nozzle opening 12 into the pathof air travelling through the draft pipe 1 under pressure and is 10preferably ignited by means'of a jump spark ignition including spacedapart electrodes. 13 supported upon the air pipe'11 and insulatedtherefrom as shown in Figure 1, the electrodes being connected by wires14 and 15 leading to an ignition device or source of electricity.

Fluid fuel atomized under pressure and in the presence of air underpressure when ignited and burning under such conditions causes adistinct noise of combustion. It is preferable to impart a whirl to theatomized fuel as it is forced out of the nozzle and a whirl in theopposite direction to the air forced out of the end of the draft pipe tomore completely mingle the oil with the proper portion of air to form acombustible mixture and it has been found that by the proper control ofthe air from the draft pipe the noise of combustion is reduced. In thisinstance the applicant has found that by terminating the draft pipe inwhat might be called a conical cap 16 which contracts the end of thedraft pipe, as shown in Figure 1, with the sides of the cap sloping atan angle of about 30 and providing the interior of the cap with aplurality of vanes 17 arranged equi-distant from each other at an angleof about 45 to the travel of the air through the draft pipe and with thelower edges of the vanes parallel to the axis of the draft pipe, a

-whirl is imparted to the air passing therethrough to contact with theopposite whirl of the atomized fuel leaving the nozzle to completecombustion and the contracted cap containing the whirl imparting vanesalso directs the air forced through the draft pipe in a downwarddirection causing it to impinge upon the opposite whirling spiral offuel in such a manner that when the fuel is ignited, the noise ofcombustion is greatly reduced.

The fuel nozzle 5 is shown in detail in Figures 4 to 9 inclusive andincludes a cylindrical casing 18 screw threaded at one end 19 to receiveand secure the air pipe 11 thereto, the opposite end of which isprovided with a closure having a convex outer surface 20 with a centraldischarge aperture or opening 12. The interior of the nozzle casing isshouldered and the intermediate portion is screw threaded to receivewhat may be termed a fuel spiral, shown in detail in Figure '7 whichincludes the cylindrical casing 21 screw threaded interiorly at one end22 to receive and secure the end of the fuel pipe 6 and exteriorly screwthreaded as at 23 to engage the screw threaded portion of the nozzlecasing 18. The other end is provided with a closure or head 24, theexterior diameter of which is less than the inner diameter of that endof the nozzle casing 18 and slightly greater than the intermediateportion of the casing 21 between the closure head 24 and the screwthreaded portion 23. The screw threaded portion 23 is provided withpreferably six longitudinal slots 25 or passageways through I which airfrom the air pipe 11 may pass to the interior of the nozzle housingtherebeyond. Two of these diametrically opposite slots may be continuedacross the end of the screw threaded portion 23 to form a tool engagingslot 26 for the proper insertion of the oil spiral within the nozzle.

The closure 24 terminates in a flat surface 2'7 at right angles to theaxis of the casing 21, the corners of which are cut away to provide asurface at a frusto conical surface 28 at an angle to the said axis tojoin the cylindrical outer surface of the main body of the closure 24.The closure of the nozzle casing 18 is formed upon the interior with acorresponding surface to be, contacted by the conical end 28 of thespiral and form a seal therewith and the nozzle closure is tapered fromthis seal to form an edge about the nozzle opening 12. A plurality ofair passages 29 are formed in the end closure. or head 24 of the fuelspiral leading at an angle to the axis of the spiral from the spacewithin the nozzle casing 18 through the flat surface 27 of the head tocommunicate with the chamber 30 formed between this flat surface and thenozzle closure behind the nozzle discharge opening 12. The bottom ofeach of these air passages 29 is connected to the interior of the airspiral casing 21 preferably by sloping fuel passageways 31 whereby thefuel from the fuel pipe 6 is caused to be contacted by the air from theair pipe 11 and oil and air are ejected from the nozzle through theopening 12. Any preferred number of air passages 29, each provided witha fuel passage 31, may be employed. Figure 9 illustrates three of suchpassages; Figure 10, four; and Figure 11, six. It is preferable toconstruct these passages 29 at an angle as shown.

It is preferable to construct the nozzle discharge opening 12 of adiameter approximately A; of an inch and the relation of the airpassages 29 in the closure head 24 and the air passages 25 in the screwthreaded portion 23 of the fuel spiral 21 so that the pressure of theair from the chamber 3 passing through the air pipe 11 will be greater,approximately one-half pound, than the pressure of the fluid fuelpassing through the fuel pipe 6. The fluid fuel as it leaves the fuelpassageways 31 will be contacted by the air under pressure forcedthrough the passageways 29 in the head of the oil spiral which willbreak the fluid fuel into parti-' cles and whirl it into the chamber 30and out over the edges of the nozzle opening 12 in the form of awhirling cone of increasing diameter.

The whirling particles of the atomized fuel unite with the air underpressure leaving the draft pipe to form a combustible mixture and when aspark is caused to jump across, the electrode 13 will ignite and burnwith a flame which remains at a fixed distance in front of the nozzleand sufliciently distant therefrom to prevent carbonization of theconvex surface 20 surrounding the nozzle opening.

While no means have been shown for supplying fluid fuel and air underpressure through the pipe 4, it is preferable to employ the means shownin the applicants said prior application, however it is not necessary tothis invention that the air under pressure and fluid fuel be deliveredin the manner described in said application. As far as this invention isconcerned, any controlled means for supplying the fluid fuel to the pipe4 and any form of air compressor for delivering air under pressurethrough pipe 4, either to the chamber 3 or to the respective air andfuel pipes directly, may be employed without departing from the scope ofthis invention.

Figure 12 illustrates a modified exterior to the nozzle 5 which includessecuring upon the outer surface of the cylindrical casing 18approximately half way between the longitudinal center and the dischargeopening 12, a ring 32 projecting outwardly from the cylindrical surfacea distance approximately equal to the nozzle discharge opening. Thisprojecting ring has the effect upon contact by the air under pressurepassing through the draft pipe 1 to divert a portion passing thereoverto sweep about the convex surface 20 of the nozzle closure whereby anyof the atomized fuel that may have become attached thereto from anycause will be immediately wiped off and will prevent any collectionthereafter so that the nozzle will be maintained free of carbonizationof the fuel while the burner is in operation.

Figure 13 illustrates a modification to the fuel spiral 21 whichincludes the provision of a conical projection 33 extending from theflat surface 2'7 of the head 24 which is concentric with the axis of thespiral casing 21, the apex of which terminates flush with the nozzleopening 12 so that the sides of the cone are spaced apart and aresubstantially parallel to the portion of the nozzle closure taperingaway from the nozzle opening 12. This conical projection acts to spreadthe flame and directs the air and oil passing thereover through thenozzle opening with a greater velocity.

What I claim is:

1. In a fluid fuel burning mechanism, a fuel pipe surrounded by an airpipe leading from a source of fuel and a source of air under pressure,respectively, to a burner nozzle, said nozzle including a tubular casingsecured at one end to the air pipe and having the other end convergingto provide a restricted discharge opening, a tubular fuel spiral of lessdiameter mounted within the nozzle casing having a transverse end wallperipherally beveled in engagement with the converging nozzle closure toform a tip chamber and having an interior chamber connected to said fuelpipe, a plurality of angular air passages tangential to the tip chamberprovided in the form of grooves upon exterior portion of the fuel spiralin engagement with the nozzle closure, and a corresponding number offuel passages leading from said chamber, each opening into one of saidair passages, whereby the fuel as it leaves the fuel passages in thespiral will be contacted by the air forced through the air passages, bebroken into particles and whirled through the nozzle opening.

2. In a fluid fuel burning mechanism, a fuel pipe surrounded by an airpipe leading from a source of fuel and a source of air under pressure,respectively, to a burner nozzle, said nozzle including a tubular casingsecured at one end to the air pipe and having the other end convergingto provide a restricted discharge opening, a tubular fuel spiral of lessdiameter having an enlarged portion provided with longitudinal airpassages therein, mounted within the nozzle casing and enlarged headhaving a transverse end wall peripherally beveled in engagement with theconverging nozzle closure to form a tip chamber and having an interiorchamber connected to said fuel pipe, a plurality of angular air passagestangential to the tip chamber provided in the form of grooves upon theexterior portion of the beveled fuel spiral in engagement with theconverging nozzle closure, and a corresponding number of fuel passagesleading from said chamber, each opening into one of said air es, wherebythe fuel as it leaves the fuel passages in the spiral will be contactedby the air forced through the air passages, be broken into particles andwhirled through the nozzle opening.

3. In a fluid fuel burning mechanism, a fuel pipe surrounded by an airpipe leading from a source of fuel and a source of air under pressure,respectively, to a burner nozzle, said nozzle including a tubular casingsecured at one end to the air pipe and having the other end convergingto provide a restricted discharge opening, a tubular fuel spiral of lessdiameter having an enlarged portion provided with longitudinal airpassages therein, mounted within the nozzle casing and enlarged headhaving a transverse end wall peripherally beveled in engagement with theconverging nozzle closure to form a tip chamber between the head andclosure and having a chamber connected to said fuel pipe, a plurality ofangular air passages tangential to the tip chamber provided in the formof grooves upon the exterior portion of the fuel spiral in engagementwith the converging nozzle closure, and a corresponding number of fuelpassages leading from said chamber, each opening into one of said airpassages, whereby the fuel as it leaves the fuel passages in thespiralwill be contacted by the air forced through the air passages, bebroken into particles and whirled through the nozzle opening.

4. In a fluid fuel burning mechanism, a fuel pipe surrounded by an airpipe leading from a source of fuel and a source of air under pressure,respectively, to a burner nozzle, said nozzle including a tubular casingsecured at one end to the air pipe and having the other end convergingto provide a restricted discharge opening, a tubular fuel spiral of lessdiameter having an enlarged portion provided with longitudinal airpassages therein, mounted within the nozzle casing and enlarged headhaving a transverse and wall peripherally beveled in engagement with theconverging nozzle closure to form a tip chamber between the head andclosure and having a chamber connected to said fuel pipe, a plurality ofangular air passages tangential to the tip chamber provided in the formof grooves upon the exterior portion of the fuel spiral in engagementwith the converging nozzle closure, and a corresponding number of fuelpassages leading from said chamber, each opening into one of said airpassages, said head provided with a concentric conical projectionterminating in line with the discharge opening, whereby the fuel as itleaves the fuel passages in the spiral will be contacted by the airforced through the air passages, be broken into particles and whirledthrough the nozzle opening.

5. ha fluid fuel burning mechanism, a fuel pipe surrounded by an airpipe leading from a source of fuel and a source of air under pressure,respectively, to a burner nozzle, said nozzle including a tubular casingsecured at one end to the air pipe and having the other end convergingto provide a restricted discharge opening, a tubular fuel spiral of lessdiameter having an enlarged portion provided with longitudinal airpassages therein, mounted within the nozzle casing and enlarged headhaving a transverse end wall peripherally beveled in engagement with theconverging nozzle closure to form a tip chamber between the head andclosure and having a chamber connected to said fuel pipe, a plurality ofangular air passages tangential to the tip chamber provided in the formof grooves upon the exterior portion of the fuel spiral in engagementwith the converging nozzle closure, and a corresponding number of fuelpassages leading from said chamber, each opening into one of said airpassages. said head provided with a concentric conical projectionentering the tip chamber between the head and the converging nozzleclosure and terminating in line with the discharge opening, whereby thefuel as it leaves the fuel passages in the spiral will-be contacted bythe air forced through the air passages, be broken into particles andwhirled through the nozzle opening.

WALTER W. WILLIAMS.

